人参皂甙Rd对皮层神经元兴奋性毒性损伤后胞内游离钙的影响  

The effect of ginsenoside Rd on the intracellular free calcium after excitotoxic injury in cultured cortical neurons

作　　者：张琛[1] 叶瑞东[1] 韩军良[1] 史明[1] 曹荣[2] 饶志仁[2] 吴昊[3] 赵钢[1] 

机构地区：[1]第四军医大学西京医院神经内科,西安710032 [2]第四军医大学神经生物学教研室,西安710032 [3]第四军医大学卫生统计学教研室,西安710032

出　　处：《神经解剖学杂志》2010年第2期112-118,共7页Chinese Journal of Neuroanatomy

摘　　要：目的:探讨人参皂甙Rd(Ginsenoside Rd,GSRd)对皮层神经元兴奋性毒性损伤后细胞内游离钙离子浓度变化的影响。方法:采用原代方法培养大鼠皮层神经元,免疫荧光染色鉴定神经元纯度。应用激光共聚焦显微镜,观察GSRd对谷氨酸(Glutamate,Glu)和N-甲基-D-天门冬氨酸(NMDA)刺激后神经元胞内游离钙离子浓度变化的影响。使用钙离子荧光探针Fluo-4,AM标记细胞内游离钙,以Fluo-4的荧光强度反映细胞内游离钙浓度变化。结果:空白对照组荧光强度没有明显变化,而高浓度Glu刺激可迅速升高神经元胞内的荧光强度;在给予GSRd干预时,荧光强度升高的幅度明显降低,与MK-801的作用相似;NMDA刺激亦可使神经元胞内荧光强度明显升高,而加入GSRd干预时,荧光强度升高的幅度较NMDA损伤组有明显减小。结论:GSRd能够抑制高浓度Glu和NMDA引起的大量钙内流,提示减轻兴奋性毒性损伤过程中的钙超载可能是GSRd神经保护作用的机制之一。Objective：To investigate the effect of Ginsenoside Rd （GSRd） on the intracellular free calcium response after excitotoxic exposure in cortical neuronal cultures. Methods：We first adopted the primary culture of rat cortical neurons and verified the purity by immunocytochemical staining. Second,using a fluorescent calcium indicator Fluo-4,AM,we measured the intracellular free calcium concentration which was represented by the fluorescent intensity. The effect of GSRd on the intracellular free calcium stimulated by glutamate or NMDA was examined with a laser scanning confocal microscope. Results：The results showed that high dose glutamate produced a sharp increase of fluorescent intensity,while GSRd markedly reduced the intracellular free calcium concentration which was similar to the effect of MK-801. Additionally,GSRd significantly lowered the increase in cytosolic calcium levels after NMDA exposure. Conclusion：These results suggested that GSRd might inhibit calcium influx stimulated by glutamate or NMDA,which indicates that attenuating calcium overload induced by excitotoxicity may contribute to the neuroprotective effects of GSRd.

关 键 词：人参皂甙RD 谷氨酸 NMDA 兴奋性毒性 钙离子 

分 类 号：R285.5[医药卫生—中药学]